EP0498306B1 - Method of preparing oxide superconducting material - Google Patents
Method of preparing oxide superconducting material Download PDFInfo
- Publication number
- EP0498306B1 EP0498306B1 EP92101571A EP92101571A EP0498306B1 EP 0498306 B1 EP0498306 B1 EP 0498306B1 EP 92101571 A EP92101571 A EP 92101571A EP 92101571 A EP92101571 A EP 92101571A EP 0498306 B1 EP0498306 B1 EP 0498306B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- oxide superconducting
- substrate
- silver
- preparing
- superconducting material
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Classifications
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N60/00—Superconducting devices
- H10N60/01—Manufacture or treatment
- H10N60/0268—Manufacture or treatment of devices comprising copper oxide
- H10N60/0801—Processes peculiar to the manufacture or treatment of filaments or composite wires
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S505/00—Superconductor technology: apparatus, material, process
- Y10S505/70—High TC, above 30 k, superconducting device, article, or structured stock
- Y10S505/704—Wire, fiber, or cable
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S505/00—Superconductor technology: apparatus, material, process
- Y10S505/725—Process of making or treating high tc, above 30 k, superconducting shaped material, article, or device
- Y10S505/73—Vacuum treating or coating
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S505/00—Superconductor technology: apparatus, material, process
- Y10S505/725—Process of making or treating high tc, above 30 k, superconducting shaped material, article, or device
- Y10S505/73—Vacuum treating or coating
- Y10S505/732—Evaporative coating with superconducting material
Definitions
- the present invention relates to a method of preparing an oxide superconducting material, and more particularly, it relates to a method of preparing an oxide superconducting material which is provided as a film formed on a substrate.
- oxide superconducting materials having high critical temperatures have been successively found and extensive study has been made in order to put such materials into practice for wires and the like.
- various methods have been studied for working such oxide superconducting materials into wires.
- an oxide superconducting wire is typically prepared by a silver sheath method of filling a silver pipe with raw material powder and properly carrying out wire drawing, rolling and heat treatment steps for obtaining a tape-type wire. This method is effectively applied to preparation of a wire, since the material can be easily elongated and a relatively high critical current density can be attained by mechanical orientation in rolling.
- the wire obtained by the silver sheath method merely exhibits a critical current density of a little less than 50,000 A/cm under a zero external magnetic field and that of about 10,000 A/cm at the maximum under a magnetic field of 1 T (tesla), which are insufficient for wide application to a cable or a magnet.
- a thin film having a critical current density of at least 4 million A/cm has been obtained.
- a thin film of such a high property can only be formed on a single crystal of an oxide such as strontium titanate.
- EP-A-0 398 374 discloses a method of fabricating an oxide superconducting wire in which a tape-type long base material consisting of a single-crystalline base material, a zirconia ceramic tape or a tape of nickel or nickel group alloy is employed. An oxide superconducting film is formed on this base material by laser ablation wherein a laser beam is directed onto a target and atoms and/or molecules scattered from the target are deposited on the base material.
- An object of the present invention is to provide a method of preparing an oxide superconducting material which can be easily elongated, with a critical current density being applicable in a wide range.
- unidirectional solidification indicates a method of unidirectionally providing a solid-liquid interface with a large temperature gradient in a process of solidifying a molten metal or alloy for preventing arbitrary formation of crystal nuclei in the liquid phase and facilitating crystal growth only in the solid-liquid interface, thereby supplying a unidirectional property to the structure.
- an oxide superconducting film which is formed on a commercially available silver single crystal substrate by laser ablation with an excimer laser attains a critical current density of about 2 million A/cm.
- an ordinary silver single crystal which is prepared by the Bridgeman method or the Verneuil's method of heat treating a plate for a long time, is restricted in length.
- a unidirectionally solidified material has no clear grain boundaries with substantially uniform in-plane crystal orientation on crystal surfaces and crystal orientation in directions perpendicular to the surfaces, although the same is inferior in crystallinity to a single crystal which is prepared by the Bridgeman method or the Verneuil's method.
- an oxide superconducting film was formed on such a unidirectionally solidified material by excimer laser ablation, the film exhibited no clear grain boundaries since the unidirectionally solidified material serving as a substrate had no clear grain boundaries.
- the as-obtained oxide superconducting film exhibited a critical current density of 2 to 3 million A/cm, which was equivalent to or higher than that of a film formed on the aforementioned commercially available silver single crystal substrate. It is estimated that the unidirectionally solidified silver employed in the present invention had a high dislocation density due to a high growth rate, whereby the dislocation density of the oxide superconducting film was increased as compared with the film formed on the aforementioned commercially available silver single crystal substrate leading to increase of pinning points, thereby implementing a high critical current density.
- critical current density represents a transportation current density which has been measured by an ordinary four-probe method under a zero external magnetic field at a temperature of 77 K (cooling temperature with liquid nitrogen), unless otherwise stated.
- a substrate is formed by a unidirectionally solidified material which can be easily elongated, and an oxide superconducting film is formed on such a substrate by a laser ablation method through which a high film forming rate is attained and the composition can be easily controlled.
- the critical current density of the inventive material is substantially equivalent to that of a conventional oxide superconducting thin film which is formed on a silver single crystal, and the inventive material exhibits properties which are equivalent to or higher than those of an oxide superconducting film which is formed on a commercially available silver single crystal.
- a substrate prepared by unidirectional solidification, which is formed of silver can be easily provided with proper flexibility.
- the present invention can be advantageously applied to preparation of a superconducting wire which is employed for a cable or a magnet. Further, the present invention is also advantageously applicable to preparation of a large-sized material such as one used in an acceleration cavity.
- a substrate of silver is prepared by unidirectional solidification.
- molten silver 2 is introduced into a heated pipe-shaped graphite crucible 1, whose lower end is brought into contact with water 3 as shown in Fig. 2, for example.
- Silver can be unidirectionally solidified by another method such as that for discharging molten silver from a nozzle, watering the discharged part for solidifying the same and continuously drawing out the solidified part in the form of a plate, for example.
- This method is particularly suitable for preparing a long substrate. According to the result of study which was made by the inventors, the critical current density of an oxide superconducting film has a tendency to rise as the temperature gradient of a solidification interface is increased.
- the substrate While the highest critical current density of an oxide superconducting film is obtained when a unidirectionally solidified substrate is employed, the inventors have also found that a high critical current density is effectively obtained also when the substrate is prepared by rolling or drawing a unidirectionally solidified plate.
- the substrate In order to increase the critical current density of the overall superconducting material including the substrate, for example, the substrate preferably has a smaller sectional area. In view of this point, it is useful to further roll or draw a plate which is obtained by unidirectional solidification for preparing a substrate having a small sectional area.
- a laser ablation method is applied in order to form an oxide superconducting film on a substrate which is obtained in the aforementioned manner.
- a laser ablation method is preferably carried out with an excimer laser of KrF (248 nm in wavelength), ArF (193 nm in wavelength) or XeCl (308 nm in wavelength).
- the present invention is applied to an oxide superconducting material of Y-Ba-Cu-O, Bi-Sr-Ca-Cu-O, Tl-Ba-Ca-Cu-O or the like.
- the effect of the present invention can be expected in any case.
- a silver substrate was prepared by a floating zone melting method shown in Fig. 3.
- a silver tape 4 of 1.5 mm in thickness and 10 mm in width was pulled up at a rate of 50 mm/min. while light was applied to both surfaces of the silver tape 4 from an infrared ray lamp 5 of 100 W and converged in a range of 1 mm in length, to form a fusion zone 6.
- the silver tape 4 was held by the surface tension of the fusion zone 6, and a tape-type silver substrate 7 of 60 cm in length was continuously obtained in this state.
- the silver substrate 7 was arranged in a film forming apparatus employing excimer laser ablation as shown in Fig. 1.
- a target 8 of a Y-Ba-Cu-O sintered body was arranged to be opposite to the silver substrate 7.
- An excimer laser beam 9 of KrF (248 nm in wavelength) was applied to this target 8.
- the silver substrate 7 was carried along its longitudinal direction, and heated by a heater 10 in a back side of the region which was opposite to the target 8.
- a Y-Ba-Cu-O oxide superconducting film was formed on the silver substrate 7 by the film forming apparatus shown in Fig. 1.
- the as-formed oxide superconducting film was 1.8 ⁇ m in average thickness with dispersion of ⁇ 4 %.
- This superconducting tape exhibited a critical current density of 2,400,000 A/cm along the overall length of 60 cm, while a critical current value of 430 A was recorded.
- a tape-type silver substrate which was similar to that of Experimental Example 1, was employed and a Bi-Sr-Ca-Cu-O oxide superconducting film was formed thereon by the excimer laser ablation method shown in Fig. 1.
- the as-formed superconducting tape was heat treated in the atmosphere at 880°C for 1 hour, to attain a critical current density of 420,000 A/cm along the overall length of 60 cm.
- the as-obtained oxide superconducting film was 1.6 ⁇ m in thickness and exhibited a critical current value of 67 A.
- Silver tapes obtained by the crucible method shown in Fig. 2 were employed as substrates. These silver tapes were 30 cm in length, 10 mm in width and 1.5 mm in thickness.
Description
- The present invention relates to a method of preparing an oxide superconducting material, and more particularly, it relates to a method of preparing an oxide superconducting material which is provided as a film formed on a substrate.
- In recent years, oxide superconducting materials having high critical temperatures have been successively found and extensive study has been made in order to put such materials into practice for wires and the like. In particular, various methods have been studied for working such oxide superconducting materials into wires.
- As disclosed in EP-A-0 310 033, an oxide superconducting wire is typically prepared by a silver sheath method of filling a silver pipe with raw material powder and properly carrying out wire drawing, rolling and heat treatment steps for obtaining a tape-type wire. This method is effectively applied to preparation of a wire, since the material can be easily elongated and a relatively high critical current density can be attained by mechanical orientation in rolling.
- However, the wire obtained by the silver sheath method merely exhibits a critical current density of a little less than 50,000 A/cm under a zero external magnetic field and that of about 10,000 A/cm at the maximum under a magnetic field of 1 T (tesla), which are insufficient for wide application to a cable or a magnet.
- Although a solution coating method is also studied for preparation of a wire, this method is extremely inferior to the silver sheath method in view of the critical current density.
- In relation to study of a thin film, on the other hand, a thin film having a critical current density of at least 4 million A/cm has been obtained. However, a thin film of such a high property can only be formed on a single crystal of an oxide such as strontium titanate.
- EP-A-0 398 374 discloses a method of fabricating an oxide superconducting wire in which a tape-type long base material consisting of a single-crystalline base material, a zirconia ceramic tape or a tape of nickel or nickel group alloy is employed. An oxide superconducting film is formed on this base material by laser ablation wherein a laser beam is directed onto a target and atoms and/or molecules scattered from the target are deposited on the base material.
- An object of the present invention is to provide a method of preparing an oxide superconducting material which can be easily elongated, with a critical current density being applicable in a wide range.
- The method of preparing an oxide superconducting material according to the present invention is defined in
claim 1. - Throughout the specification, the term "unidirectional solidification" indicates a method of unidirectionally providing a solid-liquid interface with a large temperature gradient in a process of solidifying a molten metal or alloy for preventing arbitrary formation of crystal nuclei in the liquid phase and facilitating crystal growth only in the solid-liquid interface, thereby supplying a unidirectional property to the structure.
- The inventors have found that an oxide superconducting film which is formed on a commercially available silver single crystal substrate by laser ablation with an excimer laser attains a critical current density of about 2 million A/cm. However, an ordinary silver single crystal, which is prepared by the Bridgeman method or the Verneuil's method of heat treating a plate for a long time, is restricted in length.
- On the other hand, a unidirectionally solidified material has no clear grain boundaries with substantially uniform in-plane crystal orientation on crystal surfaces and crystal orientation in directions perpendicular to the surfaces, although the same is inferior in crystallinity to a single crystal which is prepared by the Bridgeman method or the Verneuil's method. When an oxide superconducting film was formed on such a unidirectionally solidified material by excimer laser ablation, the film exhibited no clear grain boundaries since the unidirectionally solidified material serving as a substrate had no clear grain boundaries.
- The as-obtained oxide superconducting film exhibited a critical current density of 2 to 3 million A/cm, which was equivalent to or higher than that of a film formed on the aforementioned commercially available silver single crystal substrate. It is estimated that the unidirectionally solidified silver employed in the present invention had a high dislocation density due to a high growth rate, whereby the dislocation density of the oxide superconducting film was increased as compared with the film formed on the aforementioned commercially available silver single crystal substrate leading to increase of pinning points, thereby implementing a high critical current density.
- Throughout the specification, each numerical value of "critical current density" represents a transportation current density which has been measured by an ordinary four-probe method under a zero external magnetic field at a temperature of 77 K (cooling temperature with liquid nitrogen), unless otherwise stated.
- Thus, according to the present invention, a substrate is formed by a unidirectionally solidified material which can be easily elongated, and an oxide superconducting film is formed on such a substrate by a laser ablation method through which a high film forming rate is attained and the composition can be easily controlled. Thus, it is possible to efficiently prepare a long oxide superconducting material having a high critical current density. In particular, the critical current density of the inventive material is substantially equivalent to that of a conventional oxide superconducting thin film which is formed on a silver single crystal, and the inventive material exhibits properties which are equivalent to or higher than those of an oxide superconducting film which is formed on a commercially available silver single crystal. Further, a substrate prepared by unidirectional solidification, which is formed of silver, can be easily provided with proper flexibility.
- Therefore, the present invention can be advantageously applied to preparation of a superconducting wire which is employed for a cable or a magnet. Further, the present invention is also advantageously applicable to preparation of a large-sized material such as one used in an acceleration cavity.
- As to an oxide superconducting material which is watched with interest as a superconducting material requiring no employment of scarce liquid helium, it has been difficult to improve the critical current density due to a short coherence length. This problem can also be solved by the present invention, which is extremely useful for putting an oxide superconducting material into practice as an industrial material.
- The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.
- Fig. 1 is an explanatory diagram showing a laser ablation step which is included in an embodiment of the present invention;
- Fig. 2 is a principle diagram showing an apparatus for preparing a substrate by unidirectional solidification; and
- Fig. 3 is a principle diagram showing another apparatus for preparing a substrate by unidirectional solidification.
- According to the present invention, a substrate of silver is prepared by unidirectional solidification. In order to attain such unidirectional solidification,
molten silver 2 is introduced into a heated pipe-shaped graphite crucible 1, whose lower end is brought into contact with water 3 as shown in Fig. 2, for example. Silver can be unidirectionally solidified by another method such as that for discharging molten silver from a nozzle, watering the discharged part for solidifying the same and continuously drawing out the solidified part in the form of a plate, for example. This method is particularly suitable for preparing a long substrate. According to the result of study which was made by the inventors, the critical current density of an oxide superconducting film has a tendency to rise as the temperature gradient of a solidification interface is increased. - While the highest critical current density of an oxide superconducting film is obtained when a unidirectionally solidified substrate is employed, the inventors have also found that a high critical current density is effectively obtained also when the substrate is prepared by rolling or drawing a unidirectionally solidified plate. In order to increase the critical current density of the overall superconducting material including the substrate, for example, the substrate preferably has a smaller sectional area. In view of this point, it is useful to further roll or draw a plate which is obtained by unidirectional solidification for preparing a substrate having a small sectional area.
- According to the present invention, a laser ablation method is applied in order to form an oxide superconducting film on a substrate which is obtained in the aforementioned manner. Such a laser ablation method is preferably carried out with an excimer laser of KrF (248 nm in wavelength), ArF (193 nm in wavelength) or XeCl (308 nm in wavelength).
- The present invention is applied to an oxide superconducting material of Y-Ba-Cu-O, Bi-Sr-Ca-Cu-O, Tl-Ba-Ca-Cu-O or the like. The effect of the present invention can be expected in any case.
- Experimental Examples of the present invention are now described.
- In an experiment of preparing a silver substrate, it has been proved that a large single-crystalline material can be easily obtained by simply unidirectionally cooling silver. No clear grain boundaries were observed in a silver material which was prepared in such a manner, although its dislocation density was larger by at least a figure than a commercially available silver single crystal.
- A silver substrate was prepared by a floating zone melting method shown in Fig. 3. A
silver tape 4 of 1.5 mm in thickness and 10 mm in width was pulled up at a rate of 50 mm/min. while light was applied to both surfaces of thesilver tape 4 from aninfrared ray lamp 5 of 100 W and converged in a range of 1 mm in length, to form afusion zone 6. Thesilver tape 4 was held by the surface tension of thefusion zone 6, and a tape-type silver substrate 7 of 60 cm in length was continuously obtained in this state. - Crystal orientation of this
silver substrate 7 was examined through X-ray diffraction over the longitudinal direction. As the result, it was recognized that the surface was formed by (100) planes substantially along the overall length, and [011] directions were longitudinally uniform along the tape-type silver substrate 7. - Then, the
silver substrate 7 was arranged in a film forming apparatus employing excimer laser ablation as shown in Fig. 1. In this film forming apparatus, a target 8 of a Y-Ba-Cu-O sintered body was arranged to be opposite to thesilver substrate 7. An excimer laser beam 9 of KrF (248 nm in wavelength) was applied to this target 8. Thesilver substrate 7 was carried along its longitudinal direction, and heated by aheater 10 in a back side of the region which was opposite to the target 8. - Thus, a Y-Ba-Cu-O oxide superconducting film was formed on the
silver substrate 7 by the film forming apparatus shown in Fig. 1. The as-formed oxide superconducting film was 1.8 µm in average thickness with dispersion of ±4 %. This superconducting tape exhibited a critical current density of 2,400,000 A/cm along the overall length of 60 cm, while a critical current value of 430 A was recorded. - A tape-type silver substrate, which was similar to that of Experimental Example 1, was employed and a Bi-Sr-Ca-Cu-O oxide superconducting film was formed thereon by the excimer laser ablation method shown in Fig. 1. The as-formed superconducting tape was heat treated in the atmosphere at 880°C for 1 hour, to attain a critical current density of 420,000 A/cm along the overall length of 60 cm. The as-obtained oxide superconducting film was 1.6 µm in thickness and exhibited a critical current value of 67 A.
- Silver tapes obtained by the crucible method shown in Fig. 2 were employed as substrates. These silver tapes were 30 cm in length, 10 mm in width and 1.5 mm in thickness.
- A Bi-Sr-Ca-Cu-O oxide superconducting film and a Y-Ba-Cu-O oxide superconducting film were formed on these silver tapes in a similar manner to Experimental Examples 1 and 2 respectively. These oxide superconducting films were 1.7 µm and 1.3 µm in thickness respectively, and exhibited critical current densities Jc and critical current values Ic shown in Table 1.
Table 1 Jc Ic BiSrCaCuO 870,000 A/cm 147 A YBaCuO 3,120,000 A/cm 450 A - The same silver tapes as that in Experimental Example 3 were rolled into 0.2 mm in thickness, to prepare thin tape-type substrates.
- Then, a Bi-Sr-Ca-Cu-O oxide superconducting film and a Y-Ba-Cu-O oxide superconducting film were formed on the tape-type substrates in a similar manner to Experimental Examples 1 and 2. The as-formed superconducting tapes were 150 cm in length. These superconducting films were 1.9 µm and 2.2 µm in thickness respectively, and exhibited critical current densities Jc and critical current values Ic shown in Table 2.
Table 2 Jc Ic BiSrCaCuO 170,000 A/cm 32 A YBaCuO 690,000 A/cm 152 A - Although the properties attained in Experimental Example 4 were inferior to those in Experimental Examples 1 to 3 employing unidirectionally solidified substrates with no rolling, it is understood that the properties were extremely improved as compared with superconducting properties of various oxide superconducting materials such as a conventional superconducting wire prepared by a silver sheath method.
- Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, the scope of the present invention being limited only by the terms of the appended claims.
Claims (6)
- A method of preparing an oxide superconducting material, comprising the step of:applying a laser beam (9) to a target (8) of an oxide superconductor and depositing atoms and/or molecules being scattered from said target (8) on a substrate (7), thereby forming an oxide superconducting film on said substrate (7),characterised in that said substrate is a silver substrate prepared by unidirectional solidification.
- A method of preparing an oxide superconducting material in accordance with claim 1, wherein said laser beam (9) is an excimer laser beam.
- A method of preparing an oxide superconducting material in accordance with claim 2, wherein said excimer laser beam is prepared from one of KrF having a wavelength of 248 nm, ArF having a wavelength of 193 nm and XeCl 308 nm.
- A method of preparing an oxide superconducting material in accordance with anyone of the preceding claims, wherein said substrate (7) is elongated.
- A method of preparing an oxide superconducting material in accordance with anyone of the preceding claims, further comprising a step of rolling said substrate (7).
- A method of preparing an oxide superconducting material in accordance with anyone of claims 1 to 4, further comprising a step of drawing said substrate (7).
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3011126A JPH04245113A (en) | 1991-01-31 | 1991-01-31 | Manufacture of oxide superconductive material |
JP11126/91 | 1991-01-31 |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0498306A1 EP0498306A1 (en) | 1992-08-12 |
EP0498306B1 true EP0498306B1 (en) | 1996-03-27 |
Family
ID=11769326
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP92101571A Expired - Lifetime EP0498306B1 (en) | 1991-01-31 | 1992-01-30 | Method of preparing oxide superconducting material |
Country Status (5)
Country | Link |
---|---|
US (1) | US5248662A (en) |
EP (1) | EP0498306B1 (en) |
JP (1) | JPH04245113A (en) |
CA (1) | CA2060399C (en) |
DE (1) | DE69209337T2 (en) |
Families Citing this family (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5660746A (en) * | 1994-10-24 | 1997-08-26 | University Of South Florida | Dual-laser process for film deposition |
US5818097A (en) * | 1995-01-05 | 1998-10-06 | Superconductor Technologies, Inc. | Temperature controlling cryogenic package system |
US5741377A (en) * | 1995-04-10 | 1998-04-21 | Martin Marietta Energy Systems, Inc. | Structures having enhanced biaxial texture and method of fabricating same |
US5964966A (en) * | 1997-09-19 | 1999-10-12 | Lockheed Martin Energy Research Corporation | Method of forming biaxially textured alloy substrates and devices thereon |
US6027564A (en) * | 1997-09-23 | 2000-02-22 | American Superconductor Corporation | Low vacuum vapor process for producing epitaxial layers |
US6022832A (en) * | 1997-09-23 | 2000-02-08 | American Superconductor Corporation | Low vacuum vapor process for producing superconductor articles with epitaxial layers |
US6428635B1 (en) | 1997-10-01 | 2002-08-06 | American Superconductor Corporation | Substrates for superconductors |
US6458223B1 (en) | 1997-10-01 | 2002-10-01 | American Superconductor Corporation | Alloy materials |
US5857342A (en) * | 1998-02-10 | 1999-01-12 | Superconductor Technologies, Inc. | Temperature controlling cryogenic package system |
US6114287A (en) * | 1998-09-30 | 2000-09-05 | Ut-Battelle, Llc | Method of deforming a biaxially textured buffer layer on a textured metallic substrate and articles therefrom |
US6296701B1 (en) | 1998-09-30 | 2001-10-02 | Ut-Battelle, Llc | Method of depositing an electrically conductive oxide film on a textured metallic substrate and articles formed therefrom |
US6475311B1 (en) | 1999-03-31 | 2002-11-05 | American Superconductor Corporation | Alloy materials |
US10787892B2 (en) | 2018-09-19 | 2020-09-29 | Jefferson Science Associates, Llc | In situ SRF cavity processing using optical ionization of gases |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2842537B2 (en) * | 1987-09-28 | 1999-01-06 | 株式会社日立製作所 | Oxide superconducting wire and its manufacturing method |
JPH0261826A (en) * | 1988-08-26 | 1990-03-01 | Kobe Steel Ltd | Production of ultra-specular surface disk |
JP2822447B2 (en) * | 1989-05-19 | 1998-11-11 | 住友電気工業株式会社 | Method and apparatus for producing oxide superconducting wire |
-
1991
- 1991-01-31 JP JP3011126A patent/JPH04245113A/en not_active Withdrawn
-
1992
- 1992-01-30 EP EP92101571A patent/EP0498306B1/en not_active Expired - Lifetime
- 1992-01-30 DE DE69209337T patent/DE69209337T2/en not_active Expired - Fee Related
- 1992-01-30 CA CA002060399A patent/CA2060399C/en not_active Expired - Fee Related
- 1992-01-31 US US07/829,847 patent/US5248662A/en not_active Expired - Lifetime
Non-Patent Citations (1)
Title |
---|
APPLIED PHYSICS LETTERS, vol. 56, no. 26, 25 June 1990, NEW YORK, US, pages 2684-2686; E. NARUMI ET AL: 'Superconducting YBa2Cu306.8 films on metallic substrates using in situ laser deposition' * |
Also Published As
Publication number | Publication date |
---|---|
CA2060399A1 (en) | 1992-08-01 |
DE69209337T2 (en) | 1996-08-14 |
JPH04245113A (en) | 1992-09-01 |
EP0498306A1 (en) | 1992-08-12 |
DE69209337D1 (en) | 1996-05-02 |
CA2060399C (en) | 1995-12-12 |
US5248662A (en) | 1993-09-28 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP0581254B1 (en) | Method of forming single-crystalline thin film | |
EP0498306B1 (en) | Method of preparing oxide superconducting material | |
US5015618A (en) | Laser zone melted Bi--Sr--Ca--Cu--O thick films | |
US5527765A (en) | Superconducting YBa2 Cu3 O7-x produced at low temperatures | |
JP2866265B2 (en) | Method for producing high critical temperature superconducting flexible conductor | |
US5262391A (en) | Oxide superconductor and process for preparation thereof | |
US5187149A (en) | Method of making a ribbon-like or sheet-like superconducting oxide composite body | |
Yamada | Liquid-phase epitaxy processing of RBa2Cu3O7− δ | |
EP0324534B1 (en) | Method of making a superconducting ceramic body | |
US5856277A (en) | Surface texturing of superconductors by controlled oxygen pressure | |
JP3881732B2 (en) | Method for producing oxide superconductor composite | |
Levinson et al. | Laser zone‐melted Bi‐Sr‐Ca‐Cu‐O thick films | |
US5116808A (en) | Tape based on a superconducting oxide, and method of manufacture | |
Jiang et al. | The crystal growth of Y-Ba-Cu-O by laser floating zone melting | |
Nakamura et al. | LaSrGaO4 substrate for epitaxial high-Tc superconducting thin films | |
JPH02258698A (en) | Production of oxide superconductor | |
Badia et al. | Magnetic and electric transport properties of Ag/(Bi, Pb) Sr Ca Cu O superconducting fibres | |
JPH04245112A (en) | Manufacture of oxide superconductive material | |
JP3122765B2 (en) | Method for producing oxide superconductor thick film tape material | |
JPH0562546A (en) | Manufacture of thick film of oxide type superconductor | |
Itskovich et al. | A modified method for obtaining highly textured YBaCu ceramics | |
JPH04245114A (en) | Manufacture of oxide superconductive material | |
Risch et al. | Infrared-lamp zone melting on the 31 Å BSCCO phase | |
Shiohara et al. | Highly Textured Superconducting Bi2Sr2CaCu2Oy Crystals Prepared by Unidirectional Solidification Processing | |
Su et al. | The effect of starting material composition on the growth of Bi-based ribbon-like thin films |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): DE FR GB |
|
17P | Request for examination filed |
Effective date: 19920917 |
|
17Q | First examination report despatched |
Effective date: 19941012 |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): DE FR GB |
|
REF | Corresponds to: |
Ref document number: 69209337 Country of ref document: DE Date of ref document: 19960502 |
|
ET | Fr: translation filed | ||
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
26N | No opposition filed | ||
REG | Reference to a national code |
Ref country code: GB Ref legal event code: IF02 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 20080124 Year of fee payment: 17 Ref country code: GB Payment date: 20080130 Year of fee payment: 17 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: FR Payment date: 20080108 Year of fee payment: 17 |
|
GBPC | Gb: european patent ceased through non-payment of renewal fee |
Effective date: 20090130 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20090801 |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: ST Effective date: 20091030 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20090130 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: FR Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20090202 |